sapling::Builder: add funding stream outputs in a more predictable order.

Previously it was deterministic, but depended on details of the `operator<`
implementations of `FundingStreamRecipient`, `SaplingPaymentAddress`, and
`CScript`. Now it is just the same order as in `vFundingStreams`.

Signed-off-by: Daira-Emma Hopwood <[email protected]>

Author: daira

src/miner.cpp

@@ -115,39 +115,38 @@ class AddOutputsToCoinbaseTxAndSign
     }
 
     CAmount SetFoundersRewardAndGetMinerValue(sapling::Builder& saplingBuilder) const {
-        auto block_subsidy = chainparams.GetConsensus().GetBlockSubsidy(nHeight);
+        const auto& consensus = chainparams.GetConsensus();
+        const auto block_subsidy = consensus.GetBlockSubsidy(nHeight);
         auto miner_reward = block_subsidy; // founders' reward or funding stream amounts will be subtracted below
 
         if (nHeight > 0) {
             if (chainparams.GetConsensus().NetworkUpgradeActive(nHeight, Consensus::UPGRADE_CANOPY)) {
-                auto fundingStreamElements = chainparams.GetConsensus().GetActiveFundingStreamElements(
-                    nHeight,
-                    block_subsidy);
-
                 LogPrint("pow", "%s: Constructing funding stream outputs for height %d", __func__, nHeight);
-                for (Consensus::FundingStreamElement fselem : fundingStreamElements) {
-                    miner_reward -= fselem.second;
-                    examine(fselem.first, match {
+                for (const auto& [fsinfo, fs] : consensus.GetActiveFundingStreams(nHeight)) {
+                    const auto amount = fsinfo.Value(block_subsidy);
+                    miner_reward -= amount;
+
+                    examine(fs.Recipient(consensus, nHeight), match {
                         [&](const libzcash::SaplingPaymentAddress& pa) {
-                            LogPrint("pow", "%s: Adding Sapling funding stream output of value %d", __func__, fselem.second);
+                            LogPrint("pow", "%s: Adding Sapling funding stream output of value %d", __func__, amount);
                             saplingBuilder.add_recipient(
                                 {},
                                 pa.GetRawBytes(),
-                                fselem.second,
+                                amount,
                                 libzcash::Memo::ToBytes(std::nullopt));
                         },
                         [&](const CScript& scriptPubKey) {
-                            LogPrint("pow", "%s: Adding transparent funding stream output of value %d", __func__, fselem.second);
-                            mtx.vout.emplace_back(fselem.second, scriptPubKey);
+                            LogPrint("pow", "%s: Adding transparent funding stream output of value %d", __func__, amount);
+                            mtx.vout.emplace_back(amount, scriptPubKey);
                         },
                         [&](const Consensus::Lockbox& lockbox) {
-                            LogPrint("pow", "%s: Noting lockbox output of value %d", __func__, fselem.second);
+                            LogPrint("pow", "%s: Noting lockbox output of value %d", __func__, amount);
                         }
                     });
                 }
             } else if (nHeight <= chainparams.GetConsensus().GetLastFoundersRewardBlockHeight(nHeight)) {
                 // Founders reward is 20% of the block subsidy
-                auto vFoundersReward = miner_reward / 5;
+                const auto vFoundersReward = miner_reward / 5;
                 // Take some reward away from us
                 miner_reward -= vFoundersReward;
                 // And give it to the founders